Reaction #49179

Reaction equation

compound 3a

[6-(4-Hydroxy-2-hydroxymethyl-pyrrolidin-1-yl)-6-oxo-hexyl]-carbamic acid benzyl ester

Borane THF

→

compound 29

Yield 92.1%

[6-(4-Hydroxy-2-hydroxymethyl-pyrrolidin-1-yl)-hexyl]-carbamic acid benzyl ester

Yield 92.1%

Solvents

THF

Conditions

Workup

1. 1
   Otherwas brought to room temperature
2. 2
   Temperatureat reflux temperature for over night
3. 3
   Temperaturethe reaction mixture was cooled
4. 4
   Concentrationconcentrated under vacuum to dryness
5. 5
   workup.ADDITIONTo the residue, saturated solution of ammonium chloride (200 mL) was added
6. 6
   Extractionthe product extracted with ethyl acetate (3×100 mL)
7. 7
   DryingThe combined organic layer was dried over anhydrous sodium sulfate
8. 8
   Filtrationfiltered
9. 9
   Concentrationconcentrated under reduced pressure
10. 10
    OtherThe crude was purified by column chromatography over silica gel

Procedure

Referring to scheme 10, compound 3a (7 g, 19.2 mmol) was dissolved in anhydrous THF and cooled to 0° C. under argon atmosphere. Borane-THF (50 mL, 1M soln. in THF, 2.5 equiv.) was added slowly over a period of 15mins. The reaction mixture was brought to room temperature and stirred at reflux temperature for over night. After 16 h, the reaction mixture was cooled and concentrated under vacuum to dryness. To the residue, saturated solution of ammonium chloride (200 mL) was added and the product extracted with ethyl acetate (3×100 mL). The combined organic layer was dried over anhydrous sodium sulfate, filtered and concentrated under reduced pressure. The crude was purified by column chromatography over silica gel to afford compound 29 as a viscous liquid (6.2 g, 92%).

Source